76 ORTHOGENETIC EVOLUTION IN PIGEONS. 



EXPLANATION OF PLATE 24. 

 A and B. From adult female Zenaidura carolinemis (11). Natural size. Hayashi del., June 1907. 



Fio. A. 1, 2, 3, 4, four inner longer scapulars (left side). On 1 and 2 a single inner marginal spot. Asymmetrical 



spots on 3 and 4. 

 Flo. B. 5, 6, 7, 8, four inner tertials (left side). All spots of the scapular series are strengthened here, and all are 



asymmetrical, with the inner spot the stronger of the pair. 



Measurements are omitted by the editor. All spots stronger than in Zenaida (figs. 3 and 4). Compare with 

 Juvenal inner tertials, pi. 41, figs. D, E. 



C and D. From adult male Zenaida vinaceo-ruja (11). Natural size. Hayashi del., Mar. 1907. 



FIG. C. 1, 2, 3, inner longer scapulars (left side). All spots are weak, thin marginal streaks. 



FIG. D. 4, 5, 6, three inner tertials (left side). The lower (outer) spots shorter (as in scapulars), oblong or elliptical. 



No. 6 not quite so strong and definite in outline as No. 5. 

 Measurements are omitted by the editor. 



E. Third tertial from a hybrid (ZZ-A1); the sire was a hybrid Zenaida x Zenaidura; the dam was 

 a white ring-dove (St. alba). 



The influence of the dam a species that has gone far past dark centers and spots is not sufficient completely 

 to efface the spot, but levels it to its weakest form, mainly to a very thin marginal streak. 



EXPLANATION OF PLATE 25. 



Selected feathers from the Juvenal mourning-dove, Zenaidura carolinensis. Hayashi del., Feb. 1904. 



Figs. 1 to 3. Three smaller coverts (rig lit side, X 2). In Nos. 1 and 3 there is a tinge or trace of pigment on the right 

 (lower) web quite at the edge. 



Figs. 4 to 7. Scapulars from before backward to about the middle of scapular region (X 2). Black gradually appears 

 on the right (lower) web. This means that black in the center of the distal end of the feather has dis- 

 appeared, leaving an increasing trace of a lateral spot. 



The young feathers show that the clear-cut spots of the adult are probably derived from elongated 

 patches, parts of a dark center. 



Figs. 8 to 11. Tertials, or inner secondaries (right side). 



Fig. 12. Second feather in right side of the tail. 



The outlines of these spots are less distinct than in adult tertials (see pi. 24). The pale edge is 

 scarcely differentiated in these figures. 



EXPLANATION OF PLATE 26. 



A. Neck-mark of adult male white-winged pigeon, MelopeKa leucopiera. Hayashi del., Dec. 1902. 



This species has the black spot close under the auriculars; its position is the same as in the mourning-dove, but 

 is larger in the white-wing. The iridescence here is bronzy. 



The rows of feathers that are spotted in the turtle-dove are here iridescent (shown by lighter shading). It is 

 remarkable that the ornamentation in color should here be carried higher up, and that the iridescence also moves 

 up with it. The upper row of black is continued backward into iridescent feathers, and the iridescence can be seen 

 for one to two or three rows higher still, to about the upper boundary of the ear-coverts. The iridescence extends 

 downward from the uppermost black row over about 8 or 9 rows, to about the mid-height of the neck. None of these 

 black feathers of the spot have any trace of white tips. 



The feathers, through the black spot and the iridescent area, are not so sharply cut at the tips as in the turtle- 

 dove and the ring-dove, but these feathers are cut a little shorter and the barbs are a little closer and more trim 

 than feathers elsewhere. In other words, the differentiation is, though in lesser degree, similar to that of the turtle- 

 dove (X 2/1). 

 FIG. 1. First feather of second row, left (X 2.75). 



2. Mid- feather of third row, right (X 2.5). 



3. Last feather of third row, left (X 3) ; right half is iridescent. 



In this specimen there are only four rows of black feathers. A female that has just died shows five rows, and 

 I think some birds have as many as six. These feathers in favorable light exhibit a greenish or purplish or in some 

 cases an indigo iridescence. 



B. Neck-mavk of adult male mourning-dove, Zenaidura carolinensis. Hayr.shi de!., Dec. 1902. 



In this specimen I find only two rows of velvety black feathers, some of which show iridescence. 



The iridescence is purplish-red and covers the area of the turtle-clove spot and extends up to the auriculars. It 

 is represented by light shade. These feathers arc not cut so short as in the ring region of ring-doves, but they exhibit 

 some differentiation even in the structure. 

 FIG. 1 (3). Middle feather of second row. 



2 (3). Last (lower) feather of second row. 



3 (2). About four rows below the spot; shaded part is bright purplish-red. 



